Search results
Results From The WOW.Com Content Network
The process of moulting in insects begins with the separation of the cuticle from the underlying epidermal cells (apolysis) and ends with the shedding of the old cuticle (ecdysis). In many species it is initiated by an increase in the hormone ecdysone. This hormone causes: apolysis – the separation of the cuticle from the epidermis
After the old cuticle is shed, the arthropod typically pumps up its body (for example, by air or water intake) to allow the new cuticle to expand to a larger size: the process of hardening by dehydration of the cuticle then takes place. The new integument still is soft and usually is pale, and it is said to be teneral or callow. It then ...
A dragonfly in its radical final moult, metamorphosing from an aquatic nymph to a winged adult.. In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at specific times of the year, or at specific points in ...
Apolysis (Ancient Greek: ἀπόλυσις "discharge, lit. absolution") is the separation of the cuticle from the epidermis in arthropods and related groups . Since the cuticle of these animals is also the skeletal support of the body and is inelastic, it is shed during growth and a new covering of larger dimensions is formed.
The group Ecdysozoa is supported by many morphological characters, including growth by ecdysis, with moulting of the cuticle – without mitosis in the epidermis – under control of the prohormone ecdysone, and internal fertilization. [13] The group was initially contested by a significant minority of biologists.
They possess an exoskeleton with a cuticle made of chitin, often mineralised with calcium carbonate, a body with differentiated segments, and paired jointed appendages. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. They form an extremely diverse group of up ...
Keratinocytes are the main cell type of the epidermis. They form several layers of the skin. Life for a keratinocyte begins at the stratum basale layer. Cells here proliferate and move through the stratum spinosum and stratum granulosum. The topmost layer is called the stratum corneum.
The cuticle is in some cases thinner on the lower epidermis than on the upper epidermis, and is generally thicker on leaves from dry climates as compared with those from wet climates. [36] The epidermis serves several functions: protection against water loss by way of transpiration, regulation of gas exchange and secretion of metabolic ...